johnson in the back with both hands. mr. johnson fell face first to his death. seemingly contradicting that he fell by accident after graham pushed his arm away during an argument. >> the fact she openly admits she took a dear friend from us boggles my mind. >> reporter: u.s. attorneys say they plan to prove for nine days after johnson's death, graham went to great lengths to hide her crime from family and friends and law enforcement. even allegedly sending herself e-mails from a fake account she created named tony. prosecutors have to prove she intended to kill him. this was not an accident. >> reporter: graham has pleaded not guilty. in their legal briefs, they admit graham's story changed over time but maintained johnson's death was an accident. the defense also writing in its brief that despite expected testimony that graham suffered for cold feet, witnesses thought the wedding was perfectly normal. >> this case is going to come down to whether the jury believes that she really regretted this marriage so much that she really just pushed him off the edge lite